SecurityModification Property

Type

Remarks

If you enable any security feature, be sure to set the
owner password (through SecurityOwnerPassword property)
or the user password (through the SecurityUserPassword property). If
you set both passwords, they should be different.

Also bear in mind that if the user password is set but no owner
password is specified, the permission flags are ignored and full
permissions are granted for all operations. In other words, the
permission flags are only respected when there is an owner
password.

The security features can be combined in any way, but be aware
that out of the possible combinations, only five are offered by
Adobe Acrobat. The five configurations available in Acrobat (when
using 128-bit encryption) can be achieved as follows:

Acrobat "Changes
Allowed"

easyPDF SDK Flag Combination

None

PRN_SEC_MODIFY_PERM_NONE | PRN_SEC_ANNOT_PERM_NONE

Inserting,
deleting, and rotating pages

PRN_SEC_MODIFY_PERM_ASSEMBLY | PRN_SEC_ANNOT_PERM_NONE

Filling in form fields and signing existing signature
fields

PRN_SEC_MODIFY_PERM_NONE | PRN_SEC_ANNOT_PERM_FORM

Commenting, filling in form fields, and signing existing
signature fields

PRN_SEC_MODIFY_PERM_NONE | PRN_SEC_ANNOT_PERM_FULL

Any except extracting pages

PRN_SEC_MODIFY_PERM_FULL |
PRN_SEC_ANNOT_PERM_FULL

Note that once security is enabled, it is important to set the
encryption bit length (via the SecurityEncryption property) first
before specifying any other security settings. The sample code
below illustrates the proper order.